Vacuum-tube-control unit



Oct. 19,1926. 1,603551 S. D- LIVINGSTON VACUUM TUBE GONTROL UNIT Filed Sept. 12. 1923 2 Sheets-Sheet 1 IN VEN TOR 5/0/r/ey .D. (A /0751b. BY

ATTORNEY I Oct. 19,1926. 1,603,551

- S. D. LIVINGSTON VACUUM TUBE CONTROL UNIT Filed Sep t. 1923 2 Sheets-Sheet 2 v I E g mmmmml mg 3:5!

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A TTORNE Y Patented Dot. 19, 1926.

ld t l D S'llfii'lllifsi STANLEY'TD. LIVINGSTCN, .OF1"TEVT'YORK, N; Y.', ASSIGNOR'TQEISEMLANNMAGNETO COBPORAEION, O33" BROOKLYN, NEW YORK, A CORPORATION OFNEW YORK.

VAGUUM-TU'BE-CON T111013 UNIT."

Application filetLSelatember'125x1823n SerialN'o. $823.76.

lily invention relates to radio receiving.

ticularly detector units and? ampliiie'runits: Each unit is complete initseli, all parts'be attached 1 to a: panel.

In :a'detector unitconstructed in accordance with my invention, ,a single base carriesa yacuum: tube SOClCQt, a variable rheostat, amounting for a. gridilealr, and a mounting for a grid condenser.

Then my inyentionwis applied'to 'an amplifier unit,Mt-here is abase on-Whiclr are: mounted 1 a f vacuum-tube socket, a Variable rheostat, and an audio-frequency (or radiofrequency) transformer.

In the preferredconstruction Of my iii- Y'OHtiOH, the Variable rheostat is mounted in a rotatable Wheel surrounding the lamp: socket. This produces an exceedingly com pact arrangement; l fhen' the base is mounted on a panel, the periphery of: the Wheel projects through slot' in the panel. for n'iai-iipulation by the fingers. The -rotatable rheostat has a fixed acontact fingerconnected with one of the filament contacts of'the lamp socket.

In eaeh'unit the parts are completely wired, sorall the radio fan has to do it-to attach the base" to a panel, which maybe done with a couple of screws; Further more, adet-ector uni-tand anandio-trequeney amplifier unit may be i'nounted side by side on a panel and only a single Wire is need-edto connect them together;

Another advantage: residing. in my" inventioa is a short'directconneetion from the grid contactot-the lamp socket to the grid terminal of the other eleetricaLelement on the base. This prevents, or'at' least a mini-i mixes, loss'of energy and feedback action, which are liable tooccur Where the: grid lead istoo near the plate circuit.

he foregoing; and other: objects and-ad'- vantages of my invention Will become apparent from a detailed description-of the accompanying drawings; Which illustrate-a detector nnit and an audio-frequencyamplilie unit in 51 101111 Oif'CODSbIUGblOil which I have actually used and Which-I: prefer at the present time. In these drawings, whichshowthe parts in approximately full size,

Fig. 1 is-a top planwview t a:detector ing mounted on a single base, Which is easily.

unit eonstruetedin accordanceWit h my in. vention;

Fig. 2. is a bottom plan View of the unit shown in Fig. 1;

Fig. 3 is a longitudinal cross-section 0n line- 3--3 of Fig.1;

Fig. 4- is detached bottom plannview showing the mounting oi the rheostat ina: Wheelsurrounding the lamp-s0cket;

Fig.,5-is arezirend View of the unit shown in the preceding figures;

Figfi is "a side iewof an audio-free. queney unit embodying myinvention;

Fig. Tis a bot-tom-plan-view oftheam plilier: unit shown in Fig. 6

Fig. 8 is ai'iragmentary front view show ing the rheostat Wheel projecting through aslot in a plate attached. to-a supporting panel;

Fig. 9 is a Wiring diagram of the" two units in bottom plan View; :and

Fig. 10 is asection in line 10-10 of Fig. 8.

I Will first describe the detector unitshown in Figs. 15-.

All the parts are mounted on a base- B, Which may be formed o-f=a single=piece of sheet metal having side flanges 1 toincrease its rigidity. An=opening2 is provided-Ion the base-near the front edge thereof, for a; purpose? to be. presently explained The flanges 1 terminate in a'pair of perforated. legs 3 at the frontedge of the-base plate. In fact, these lugsmay be said to constitute the tront edge ot the base plate-B, as may be seeniromFigs. lvandflv To secure the entire unit'to a panel 14, itis only necessaryto insert a pairoi screws orbolts through the panel and the holes inlugs 3, as -illus-. trated in'l igs. 1, 3 and 8. It'necessary, the rearend of the baseplate may be supported by a poster sleeve 6, througlrwhich passes a screw'iinto the bottom 8-oi' the=box 0r cabinet containingthe radio set.-

On thebase B is mounted a vacuum-tube socket (usually calledadamp-socket), indicated as a Whole by V. Thiswsocketcomprises a sylindi'ical shell Qnnda-set-ot four insulated contacts, which Lhave numbered. 10,-1.1, Hand- 13. These insulated contacts, which i are preferably resilient or resiliently mounted, extend across the opening 2 and so permit-connections to be made at then-rider'- side 0'1 the base, as "will subsequently; be de-; scribedi Contacts and :11 are thetwo filament contacts, 12 is the grid contact, and 13 is the plate contact. As will be understood, these four contacts are arranged to engage the terminal posts or a vacuum tube when the same is properly inserted into the shell 9. It is usual to provide a bayonet slot in the shell 9 for receiving a lug projecting laterally from the base of the lamp, so as to insure the correct positioning of the lamp in the socket. The connections between the socket CODtflCJS and the lamp terminals are diagrammatically indicated in Fig. 9, where 7 represents the filament, g the grid, and p the plate or: the lamp.

The form of lamp socket herein shown, particularly as relates to the mounting of the contacts, is in accordance with my invention as disclosed in my co-pending application Serial Number 908,214, filed December 21, 1922, and I do not, therefore, claim such construction in this case. In the broader aspect of my invention, the particular form of lamp socket is in'imaterial, for it is obvious that any practical type of socket may be mounted on the base plate B. I need not, therefore, describe in detail the construction and mounting of the socket contacts 10, 11,

12 and 13, since reference may be had to my aforesaid co-pending application for such details.

Around the base of lamp socket V is fixed a thin metal ring 14, which may conveniently be secured to the base plate by rivets 15, which in this instance also fasten the socket contacts to the base. The ring Ll is provided at its upper edge with an outwardly extending flange 16 having a lug 17, as best shown in Fig. 1.

Surrounding the ring 1% is a rotatable hand wheel indicated as a whole by IV. The flange 16 of ring 1 1 holds the wheel in proper position on the base without interfering with its easy adjustment by the lingers of the operator. The wheel IV is preferably formed of a single piece of insulating material, such as bakelite, or any moldable composition suitable for that purpose. As may be seen from Figs. 3 and 4;, the underside of the wheel is formed with an outer flange 18 and an inner flange 19, which provide a circular chamber or recess 20 adapted to receive a rheostat indicated as a whole by It.

In the drawings, the rheostat R is shown in the form of a coil of wire wound on red 21, but-any other practical form of resistance unit may be used. A contact finger 22, preterably resilient is secured at one end to the filament contact 10 and is arranged to bear constantly against the rheostat It, whereby one end of the rheostat is permanently connected to the filament contact 10. The other end of the rheostat is suitably grounded. In the present instance I have shown contact member 23 secured to the rod 21 and connected to the grounded end of the rheostat.

The contact member 23,'which may consist of a pair of s )ring lingers, as shown in Fig. 4, projects through a cutaway section 24. of the flange 19 of wheel IV into contact with the ring 14:. Since the ring 1 L is connected to the metal base l3 without being insulated therefrom, the contact member 23 always holds one end of the rheostat grounded to the base of the unit.

As seen in Fig. 1, the outer edge or periphcry of the rheostate wheel IV extends beyond the fastening higs 3. In order, therefore, to accommodate this projecting portion of the wheel when the base is attached to a panel, as previously explained, the panel is provided with a slot of such dimensions as to receive the projecting edge of the wheel. Figs. 1- and 3 show the wheel IV projecting through a slot in the panel 4. The outer periphery oi? the wheel is preferably knurled or roughened to permit easy turning of the wheel by the lingers- A suitable scale or index 26 may be marked on the outer rim ot the wheel, as shown, -for the purpose of indicating the amount or proportion 01". resistance cut out.

The rotary movement of hand-wheel IV in either direction is limited by suitable stops. In the embodiment shown in the drawings, the upper surface of wheel IV is provided with a lug or stop 17 arranged to engage the lug 17 on the fixed ring 1 1 when the wheel is in full on and full off position. In Fig. 1, the stop 17 abuts against the left side of lug 17, and the operator knows that the entire rhcostat is cut out. IV hen the wheel is turned until the stop 17 strikes the other edge or the lug 17, the full resistance is included in the circuit. Any other suitable means may be employed for limiting the rotary movements of the rheostat wheel IV.

On top 01. base B are mounted three supports, which in the present instance are shown in the form of sheet metal clips 27, 28 and 29. The clip 27 is secured to an in sulated binding post 30 at the underside of the base plate and projects upwardly through an opening 31. Similarly, clip 28 is secured to a binding post 32, and clip 29 to binding post 33. Binding post 32 is suit ably insulated from the metal base B, but binding post 33 is electrically connected to the base. Therefore, the clips or supports 27 and 28 are insulated, but support 29 is grounded to the base.

As best shown in Fig. 5, clip 27 has a pair of holes 34: and 35, clip 28 has a hole 36. and clip 29 has a hole 37. The supports 27, 28 and 29 are so constructed and arranged that a standard fornr or make of grid condenser is readily inserted in the openings 24- and 36, and a grid leak is similarly supported in the holes 35 and 37. Grid leaks and grid condensers usually come in the Ill 'corc ant-c with my invention.

shape ofcartridges, which may easilybe snapped into placebetween the spring'clips, as stated. In Fig. 9, agrid condensenis diagrammatically indicated at K and a grid leak at L. The grounding of binding post 33 is diagrammatically indieated'at'rc, and the grounding of one end ofthe rheostat R is similarly indicated at y.

From the underside of base plate B project two insulated binding posts 38 and 39. A metal'strip $0 of good contacting material is at one end connected: to filament contactll and 'at the other end to binding post 38. Similarly, a conducting strip ll'connects plate contact 13 with binding post 39. A conducting strip 42 leads directly from grid contact 12 to the insulated binding post 30, to which the supporting clip 27'is connected, as previously explained. In this way, one end of'the grid condenser and one end of the grid leak are electrically connected to the 'grid contact 12of the lamp socket.

It is advantageous in radio receiving sets to have the grid connection as direct as'pos sible. It the grid lead is near a plate sircuit, there is liable to'be regeneration or feed-back action, which sometimes (auses howling. In theconstruction ofmy invention, the grid connection 42 is short and direct, thereby obviating'the objections and disadvantages just mentioned.

In order to prevent accidental contact of conductors 4:0,41'and 42 withthe metai base plate B, there is interposedan insulating sheet d3. which may be a piece of bakeiite or other suitable insulating material.

In Figs. 6 and 7, Ihave shown an audiofret uency amplifier unitconstru'cted in aci This amplitier unit differs from the detcctorunit in havingv an audio-frequency transformer T mounted on the base plate in lieu otthe' supports 27, 28 and29. The lamp socket V and rheostat wheel l/V with their associated parts are the same as those described in connection with the detector unit, and I need not, therefore, repeatthis detailed description. I need only describe the details of the mounting and connections of the transformer T. The outer casingof'the transformer re over an opening 44 in the baseplate. An insulating disk 45 projects into the opening: and at its outer edge 45 bears against the underside of the base plate, as may be seen in Fig. 6. A rod ifi passes through the trans former casing and tllIOUQll the disk By tightening the nut 4-7 on the inner end of rod'dfi, the transformer casingand disk 45 are rigidly clamped against the opposite sides of the base plate, wherebythe trans "former is firmly held in position on the base ofthe unit.

I have not considered it necessary to show the interior construction of the trans former, because my present invention is not limited to anyspecific form or type of transformer. The transformer shown in Fig. 6' happens to be constructed in ae= cordance witli the invention" disclosed" in my co-pendi'ngapplication Serial Number 608,215, filed December 21, 1922, to which reference may behad-for full structural details- From the insulating disk 45 projectfour terminals or binding posts 48, d9, *and 51.- Terminals48 and d9 are connected to the primary winding ofthe transtormer; as diagrammatically indicated on therightside of Fig. 9. Terminal 51 isconnected by aconducting strip 42 to the grid terminal 12" of the lamp socket V. Terminal 50 iscon nected tothe insulated binding post 38'- by a conductor 52.

I neednot refer specifically to the other parts designated in Fig. 7 by reference numerals with prime marks because those parts are the same as correspondingly numbered parts without prime marks in Fig. 2. The same applies to the two halves of Fig. 9, where corresponding parts have the same reference number; except that-"in the right half of the frequency amplifier unit), I use" prime marks with reference numerals tor-the sake of distinction.

It will be seen from Fig. 9', that when the two units are used in the same receiving set, the only electrical connection necessary between the two is. awn-e 53 leading from binding post 39 of the detector unit to binding post 48 of the amplifier unit.

In Fig. 8 I have aplate 54; securedover the slot 25 of panel 4. This plate, which may conveniently be stamped out of sheet metal, has a slot 55 in register with the panel slot 25 and adapted to receive the project ing edge of the rheostat wheel W. The slot 55 is preferably so shaped that it widens and recedes from the center point 56' toward the two ends. Fig. 8 shows the widened ends of slot 55 and Fig 10 shows how the ends recede at 57 through the panel slot 25. .The advantage of these widened and receding'ends of slot- 55 is to allow more finger space in manipulating the wheel by hand. At the same time, the narrowed center 56 of slot 55 forms an index point for the scale 26 on the rheostat wheel W. If desired, a mark 58 may be applied at the center of slot 55 nearest the scale oi the rheostat wheel.

It is clear from the foregoing description that I have provided a vacuum-tube control unit of simple and compact construction, with all parts mounted on a single base and completely wired, requiring only a pair of screws to attach it to a panel. The only connections which the user-need to makeare the battery leadsi Asthesc connections are figure (the audio- -touched by the fingers for easy well understood, I have not deemed it necessary to show or describe them. The connection between the detector unit and audio amplifier unit may be a simple wire or it may be a connection with jacks.

It will be noticed that all binding posts and connections are at the underside of the base plate, where they are concealed from view and yet readily accessible. This enhances the neat appearance of the unit as a whole.

Although I have shown and described certain specific constructions, I would have it under-stood that I have done so merely to explain my invention and not by way of limitation. It is obvious that the broad features of my invention may be mechanically embodied in other constructions than herein set forth, without departing from the scope of my invention as defined in the appended claims.

I claim as my invention:

1. A radio unit comprising a base, a vacuum-tube socket mounted on said base, contacts for said socket, a rotatable wheel surrounding said socket, and having an outwardly projecting rim arranged to be adjustment of the wheel, a resistance element carried by said wheel, and a radially extending contact finger engaging said resistance element, said contact finger being electricaliy connected with one of the filament contacts of said socket.

2. A radio unit comprising a base, a vacuum-tube socket mounted on said base, contacts for said socket, a rotatable wheel surrounding said socket, and having an outwardly projecting rim arranged to be touched by the fingers for easy adjustment of the wheel, a resistance element carried by said wheel, a radially extending contact finger engaging said resistance element, said contact finger being electrically connected with one of the filament contacts of said socket, and stops to limit the rotary movement of said wheel.

3. A radio unit con'iprising a base, a vacuum-tube socket mounted on said base, contacts for said socket, a rotatable wheel surrounding said socket and provided with a circular recess, said wheel having an outwardly projecting rim arranged to be touched by the fingers for adjustment of the wheel, a resistance element mounted in said recess, and a contact linger engaging said resistance element, said contact finger being electrically comiected with one of the filament contacts of said socket.

4. A radio unit comprising a base, a vacuum-tube socket mounted on said base, contacts for said socket, a rotatable wheel surrounding said socket and provided with a circular recess, said wheel having an out wardly projecting rim arranged to be touched by the fingers for easy adjustment of the wheel, a resistance element mounted in said recess, a contact finger engaging said resistance element, said contact finger being electrically connected with one of the filament contacts of said socket, and stops to limit the rota y movement of said wheel.

5. In a radio unit, the combination with a vacuum-tube socket, of a rotatable rheostat surrounding said socket, and having an outwardly projecting annular rim arranged to be touched by the fingers for easy adjustment oi the rheostat, and .a contact finger for said rheostat.

6. In a radio unit, the combination with a vacuum-tube socket having the usual contacts, of a rotatable rheostat surrounding said socket and having a contact finger con nected to one of the filament contacts of said socket, and an outwardly projecting annular rim provided on said rheostat. so that the same may be engaged by the fingers for easy adjustment of the rheostat.

7. In a radio unit, the combination with a supporting panel having a slot, of a base secured to said panel, a rotatable wheel mounted on said base and so arranged as to project edgewise through said slot for manual adjustment, a resistance element carried by said wheel, and a fixed contact finger for said resistanceelement.

In a radio unit, the combination with a supporting panel having a slot, of a base secured to said panel, a vacuum-tube socketmounted on said base, contacts for said socket, a rotatable wheel surrounding said socket and so arranged on said base as to project edgewise through said slot for manual adjustment, a resistance element carried by said wheel, and a contact finger connected to one of the socket contacts and engaging said resistance element.

9. A radio unit comprising a metallic base, a vacuum-tube socket mounted on said base and having the usual contacts, a rotatable wheel surrounding said socket, a resistance clement carried by said wheel and having one end grounded to said base, and a contact finger electrically connected to one ot the filament contacts of said. socket and arranged to engage said resistance element,

10. A vacuum-tube control unit comprising a sheet metal base provided at the front edge with lugs whereby said base is horizontally attached to a vertical supporting panel, a vacuum-tube socket on said base, contacts for said socket, a rotatable wheel surrounding said socket and projecting edgewise forwardly beyond said lugs, a resistance element carried by said wheel, and a fixed contact finger for said resistance element, said finger being electrically connected to one of the filament contacts of said socket.

11. A radio unit comprising a base plate,

logs

.sulati n ing said socket, a circular recess in the underside of saidwheel, a resistance element in d recess, four conducting strips rigidly connected to the socket contacts at the underside of said base plate, the strip which is connected to one of the filament contacts being arranged to engage said resistance element, three bindin posts at the underside of said base plate, and means for connecting the other three strips to said binding posts.

wheel, a: contact finger -for said resistance.

element, and stop on said wheel arranged to engage said lug.

13. ,A radio unit comprising a base, a vacuum-tube socket= mounted on said base, contacts for said socket, a rotatable wheel surrounding: said socket, a resistance elementcarried by said wheel, a contact finger engaging said resistance element, said contact finger beingelectrically connected with one of the filament contacts of said socket, agrounded metal ringaround saidsocket, anda conductor connected to one end of said resistance element and permanently in contact with said grounded ring.

14. In a radio unit, a-metal base, a vacuum-tube socket mounted on said base and provided withicontacts, ,a metal ring fixed Orr-said base and surrounding said socket, said ringbeing grounded to said base, aninwheelimounted on said base and surroundi ngsaid ring, a flange on said ring for holdi said wheelinposition,a resistance element mounted'on said wheel, a conductingimember' connected to one end of said resistance element and'sli'dably engaging said ring as the wheel is rotated, where by said end of the resistance element is grounded to said metal base, and a contact finger connected to one of the filament contacts of said socket and slidably engaging said rheostat.

15. In a radio unit, a metal base, a vacuum-tube socket mounted on said base and provided with contacts, a metalring fixed on said base and surrounding said socket, said ring being grounded to said base, an insulating wheel inounted on said base and surrounding said ring, a flange on said ring for holding said wheel in position, a resistance element mounted on said wheel, a conducting member connected to one end of said resistance element and slidably engaging said ring as the wheel is rotated, whereby said end of the resistance element is base, a vacuum-tube ranged to be engaged by grounded to said metal base, a contact finger connected to one of the filamentcontacts of said socket and slidably engaging said re sistance element,- a lug on said ring, and a stop on saidwheel arranged to engage said lug for limiting the rotary movementof thewheel. v

16.' A radio unit comprising a base, a vacuum-tube socket mounted on said 'base',-c0ntacts tor 'said socket, a rotatable wheel surrounding said socket, a resistance element carried bysaid wheel, a contact fingerTengaging said resistance element, said contact finger being electrically, connected with one of the filament contacts of said socket, and means for grounding oneend of said resistance element to said base.

I 1.7. A radio unit comprising a base,]a va0:" uunrtub'e socketmounted on said base, contacts for said socket, a rotatable wheel'sur-- rounding said socket and provided with] a pair of spaced circular flanges which form a circular recess, a resist'ancefelement mounted in said recess, a contact finger-electrically connected with one of the filament contacts of said socketand arranged to en} gage said resistance element, a metallic member grounded to said base an'd aconductor connected to one end of saidfresistance element and extending into sliding contact with} said grounded member.

18. A. radio'unit compri'singa base, a vacuum-tube socket-mounted on said base, contacts for said socket, a rotatable wheel surrounfding said socket and provided with a pair of spaced circular flanges which form a circular recess, one of said flanges having a cutaway section, a resistance element mounted in said recess, a contact fingerelectricall'y conn'ected'witlr one of of said socket and arranged to engage said 7 resistanceelement, a metal ring surrounding said socket and grounded tdsaid'basez, and acon'ductor i connected to one end of said resistance elei'nent and extending through said cutaway section into-s1i-d-ing-coatact with said grounded rin 19. As a new article of manufacture for use in vacuum-tube control units, an insulattube socket and provided with an open circular recess on one side thereof, said wheel being also provided with an outer rimarthe fingers for easy rotation of the wheel, substantially as and for the purposes specified. V

20. As a new article of manufacture for use in vacuum-tube control units, an insulating wheel adapted to fit around a vacuum-tube socket and provided with a circular recess on one side thereof, the other side of said wheel having a scale or index,

the filament contacts 111g wheel adapted to fit around a vacuum-,

substantially as and for the purposes speciuse in vacuum-tube control units, an insulating wheel adapted to fit around a vacuumtube socket and provided with a circular recess on one side thereof, the other side of said wheel having a circular beveled portion provided with a scale or index, substantially as and for the purposes specified.

22. As a new article of manufacture for use in vacuum-tube control units, a flat wheel made of one piece of insulating ma terial and constructed to fit rotatably around a vacuum tube socket, said wheel having a pair of concentric circular flanges arranged in a common plane at right angles to the axis of the wheel, said flanges forming between them an annular chamber which is closed at one side and open at the other, substantially as and for the purposes spec-- ified.

23. As a new article of manufacture for use in vacuumtube control units, an insulating wheel adapted to fit around a vacuumtube socket and provided on one side with a pair of spaced flanges which form a circular recess, the outer flange being roughened andthe inner flange having a section cut away, substantially as and for the-purposes specified.

24. As a new article of manufacture for use in vacuumtube control units, a flat wheel made of one 'piece of insulating material and constructed to fit rotatably around a vacuum tube socket, said wheel having a pair of concentric circular flanges arranged in a common plane at right angles to the axis of the wheel,'said flanges forming between them an annular chamber which is closed at one side and open at the other, and a resistance element mounted in said annular chamber and open to the air.

25. As a new article of manufacture for use in vacuum-tube control units, an insulating wheel adapted to fit around a vacuumtube socket and provided with a circular recess on one side thereof, the other side of said wheel having a circular beveled portion provided with a scale or index, and a resistance element mounted in said recess, sfubstantially as and for the purposes spec; i ied.

26. As a new article of manufacture for.

use in radioreceiving sets, a plate adapted to be attached to a panel and having an elongated slot or opening which wldens from the center toward the sides, the edge of the plate extending rearwardly from the center of said opening toward the widened sides thereof, substantially as and for the purposes specified.

27. In a vacuum-tube control unit, a panel having an elongatedslot, a plate mounted on said panel and having an opening which registers with said slot, said plate being so constructed that the opening thereof widens from the center toward the sides, the edge of the plate extending rearwardly from the enter of said opening toward the widened sides thereof,.an adjustable member projecting edgewise through said opening in the plate, said widened and. receding portions of the opening providing increased finger space to permit easy manipulation of the member. and an electrical element controlled by said member. 1

28. In a vacuum-tube control unit, a panel having an elongated slot, -a plate mounted on said panel and having an opening which registers with said slot, said plate being so constructed that the opening. thereof widens from the center toward the sides, the edge of the plate extending rearwardly from the center of said opening toward the widened sides thereof, a wheel projecting edgewise through said opening in the plate, said widenedand receding portions of the opening providing increased finger space to permit easymanipulation of the wheel, and an electrical element controlled by said wheel.

- STANLEY D. LIVINGSTON. 

